Variocoupler



June 2, 1925. 1,540,145

H. REIFEL VARIQCOUPLER Filed May l, 1925 Patented June 2, 1925.

UNITED STATES PATENT OFFICE.

HARRY REIFEL, 0F NEW YORK, N. Y., ASSIGNOR TO PATHE PHONOGRAPH AND RADIO CORPORATION, A CORPORATION OF NEW YORK.

VARIOCOUPLER.

Application l'ed May 1,

T0 all whom t may concern:

Be it known that I, HARRY REIFEL, a citizen of the United States, residing at New York city, in the county and State of New York, have invented ce-rtain new and useful Improvements in Variocouplers, of which the followingl is a specification.

My invention relates broadly to radio telegrapliy and telephony, and more particularly to a construction of variocoupler employed in tlie electrical circuits of such systems.

One of the objects of my invention is to provide an inexpensive constructionot variocoupler for a radio receiving apparatus capable of quantity production in which the primary and secondary coils are constructed in substantially similar form.

Another object of the invention is to provide a construction of variocoupler in which tine degrees of adjustment in coupling may be secured from minimum to maximum values of coupling.

Another object of the invention is to provide a construction of rotatable shaft wholly positioned within the circumference of the primary and secondary windings and offset from the centers thereof within portions of the primary and secondary coil supports whereby lthe variocoupler may be mounted within a limited spacek in a radio receiver, permitting allocation of the associated tuning condensers and electron tube and transformer mountings therearound within a minimum area.

Other and further objects of the invention will be understood from the following speciication by reference to the accompanying drawings, in which:

Figure 1 is a partial cross sectional view, on the line 1-1 of Fig. 2, of my variocoupler mounted with relation to a panel of the radio receiving apparatus and showing the rotatable shaft mounted for controlling the degree of coupling between the primary and secondary windings; Fig. 2 is a front View of my variocoupler showingthe primary coil support in full line and the sec ondary coil support in dotted line in a position of coupling between maximum and minimum values; Fig. 3 is a perspective view illustrating the primary and secondary coils adjusted in a degree of coupling between minimum and maximum values; Fig. 4 is a partialsectional view taken through Heretofore in the art variocouplers have been relatively expensive in manufacture due, among other things, to the differently constructed forms required for the primary and secondary windings and the relative mechanical arrangement of the coil snpports for varying the degree ot coupling from maximum to minimum value.

The mechanical means by which the primary and secondary coils of a variocoupler have been adjusted relative to each other has heretofore required a substantial amount of space in the radio receiver, and with the rapid development of the art and the increase in demand for simplified broadcast receiving apparatus for the home it is important that the size of the apparatus be reduced to a minimum without sacrificing the operating qualities of the instruments. In my present construction of variocoupler I employ identical forms of coil supports for` both the primary and secondary coils and mount these supports with a rotatable control shaft arranged 'to vary the'degree of coupling between the primary and secondary in such manner that the shaft and all of its operating parts are positioned within the circumferences of the windings with no obstructing parts to interfere with adjacent apparatus. The secondary coil may be varied in a range of 180 with rela Ation to the primary coil in adjusting the degree of coupling within the range of minimum and maximum coupling.

Referring more particularly to the drawings, reference character 1 indicates a panel on which the variocoupler may be mounted.

The primary coil support is represented at 2, `and the vsecondary coil support at 3, the supports being identical in construction.

vThe supports are substantially cylindrical in form with a supporting rim `for the primary and secondary windings 8 and 9 and chordal projected portions 5 and 6 across the interior of a part of the rim.4 The primary coil support 2 is mounted upon the rear of panel 1 by means of bolts 10 extending through apertures 11 having countersunk portions 12 in th coil support 2, the bolts 10, passing through bushings 14 mountedv in countersunk portions 15 of coil support 2, and finally terminating in a threaded end 16 over which the securing nut 17 is threaded. The bolts 10 may form the terminal posts for the primary winding. A shaft 18 having control knob 19 thereon passes through panel 1 and through chordal p'ortions 5 and 6 of primary coil support 2 and secondary coil support 3 respectively. Sleeves 20 and 21 are positioned in the bores in the coil supports 2 and 3 but do not extend the entire width of the support. 'A shoulder 22 is formed on the shaft 18, and the portion.

24 of the shaft having ay reduced cross seci'f tion from other portion or section 25v is passed through sleeve 21 and secured by nut 26 fixed upon the threaded end 27. Concentrically arranged around shaft 18 and yieldingly disposed between sleeves 20 and 21 I provide a coil spring 28 which permits rotation of the shaft 18 to move the `secondary winding 9 in either loose, close or intermediate coupling adjustment with relation'to the primary winding 8. A bushing 29 is placed over shaft 18 with a set screw 3() bearing thereagainst to properly space the secondary coil support 3 with relation to the primary coil support 2. Terminals for the secondary winding 9 are provided by means of bolts 31 extending through apertures 32 and countersunk portions 33 andA 34 of the secondary coil support 3. Binding posts 35 are provided for connection of the secondary with the other arts of the equipment.

I have illustrated my variocoupler in Fig. 5 in connection with a radio frequency amplifier 36, detector 37, and audio frequency amplifier 38. The primary winding 8 is series connected with an antenna 39, condenser 40, and ground 41, and the secondary winding 9 is connected to the radio rcceiving apparatus. The degree of coupling between the primary and secondary is adjusted by rotation of knob 19, close coupling bein secured with the coils axially related, and Ioose coupling being secured with the coils positioned at 180. The coils may be ta ped as represented at 42 and connections ta en to a set of switch contacts to vary the effective number of turns in the circuit.

While I have shown my variocoupler connected in a radio frequency amplification circuit, it will be understood that it may be used in any electrical circuit and particularly as a tickler between the grid and plate circuits of an electron tube regenerative detector, and I intend no limitations upon my invention other than those imposed by the sco e ofthe appended claims.

aving thus described my invention,

what I claim and desire to secure by Letters Patent of the United States is:

.1. A variocoupler comprising in combination a pair of similar, hollow cylindrical coil supports, a chordal portion interior` of each of said supports, and a rotatable shaft passing through said chordal portions whereby one of said coils may be positioned in axial alignment with the other of said coils and rotated out of alignment therewith whereby the coupling between said coils is varied.

2. A variocoupler comprising in combination a plurality of coil supports, separate windings carried on each of said sup orts, a chordal portion interior of each oPSaid supports, terminal members mounted interiorly of each of said chordal portions and connected to said windings, and a rotatable shaft passing through said chordal portions for moving the windings into and out of coaxial relation, whereby the coupling of said windings is mutually varied.

3. A variocoupler comprising a pair of similar coil supports, each of said supports having a rim, a winding carried on thc exterior of said rim, a chordal portion on the interior of said rim, a bearing member extending through each of said chordal portions, and a shaft passing through said bearing members whereby the coupling of said windings may be mutually varied by aligning and displacing said coils from alignment.

4. A variocoupler comprising in combination a plurality of coil supports, separate windings carried on each of said supports, a chordal-portion interior of each of said supports, terminal posts carried by each of said chordal portions and connected to said windings, bearing sleeves in said chordal portions, and a rotatable/ shaft passing through said sleeves for axially aligning and displacing from alignment said windings whereby the coupling of said windings is mutually varied.

5. A variocoupler comprising a pair of similar coil supports, each of said supports having a rim, a winding carried on the exterior of said rim, a chordal portion on the interior of said rim, bearing members extending through said chordal portions and comprising sleeves having a length less than the width of said supports, and a shaft passing through said bearing members whereby the coupling of said windings may be mutually varied by aligning and displacing said coils from alignment.

6. A variocoupler comprising a pair of similar coil supports, each of said supports having a rim, a winding carried on the exterior of said rim, a chordal portion on thc interior of said rim, bearin 'members extending through said chorda portions and comprising sleeves having a length less than the width of said/supports, a shaft passing through said bearing members, and a coiled spring concentrically arranged over said shaft and yieldingly disposed between the adjacent ends of said sleeves whereby the coupling of said windin s may bemutually varied by aligning and isplaoing said coils -from alignment.

7. A varioooupler comprising in combination a pair of similar cylindrical coil supports, a chordal portion interior of each of said supports, a rotatable shaftI passing v through said chordal portions, andresilient means yieldingly disposed between said supports whereby one of said coils may be po-.

sitioned in axial alignment with the other of said coils and rotated out of alignment `therewith and` maintained in a selected posupports' lfor said windings, a bearing member in each support, means for rigidly mounting one of said supports, a rotatable shaft passing through each of said bearing members interiorly of said windings, said shaft having a smaller cross sectional area throughout one portion of its length than another portion, said first mentioned portion fitting within said other support, and resilient means between said bearing members whereby said supports may be'axially displaced for varying the coupling between said windings. p

In testimony whereof, I have aiiixed my signature.

HARRY REIFEL. 

